I just got an e-mail from supersmart saying the same thing....that they were out of stock of DMSA (which was what I was expecting), and will get some more in 10 days and so I would have to wait about 15 days for my order to arrive (which I wasn't expecting!). If they said they same thing to you last week then I should only have to wait week or less for mine to arrive after they got a new stock in!
Have you checked whether your payment went through? I'm getting worried now!